Diversity and host-networks of saproxylic beetles along a forest recovery gradient in the tropics

Titelangaben

Falconí-López, Ana ; Grella, Nina ; Donoso, David ; Feldhaar, Heike ; Huszarik, Maike ; Müller, Jörg:
Diversity and host-networks of saproxylic beetles along a forest recovery gradient in the tropics.
In: Forest Ecology and Management. Bd. 619 (2026) . - 124102.
ISSN 0378-1127
DOI: https://doi.org/10.1016/j.foreco.2026.124102

Angaben zu Projekten

Zugehörige Forschungsdaten

• Supplementary data

Abstract

The high tree diversity in tropical forests promotes the diversity of phytophagous insects, a principle that should also apply to wood-inhabiting organisms and their interactions with host tree species. However, how forest regeneration affects these relationships remains unclear. As tree biomass, diversity, and deadwood diversity increase during post-agricultural recovery, we hypothesized that saproxylic beetle abundance, species richness, and network complexity would also increase, whereas host-tree specialization of networks would decrease because greater resource availability may allow beetles to exploit a broader range of hosts. To test these hypotheses, we placed logs from five tree species differing in wood density, a key trait influencing deadwood colonization and decomposition dynamics, in 62 plots across four stages of a recovery chronosequence within a small-scale agricultural matrix of the Ecuadorian Chocó. The abundance (P < 0.001) and species richness (P = 0.01) of saproxylic beetles emerging during six months from the logs increased significantly along the forest recovery gradient. Taxonomic and network link γ-diversity also increased, particularly between agricultural plots and forest stages. Network specialization varied along the chronosequence but was higher in agricultural and late regeneration plots. Logs of low-density tree species harboured fewer individuals but higher γ-diversity, possibly because softer substrates provide more heterogeneous colonization opportunities for rare species. Our results indicate lower abundance, taxonomic diversity, and network complexity of saproxylic beetles in agricultural areas, but rapid recovery following forest regeneration and canopy closure. These findings highlight the conservation value of secondary tropical forests for restoring deadwood-associated biodiversity and ecological functions.